If you've ever wondered which part of your brain thinks about a particular object, activity or concept, worry no longer—this interactive brain is about to answer all your questions.

This online app lets your peer into a wealth of fMRI data, which has been organized to show information about how thousands of objects and actions are represented across human neocortex. The data was gathered during fMRI scans of a participant who sat through hours of movie trailers while their thoughts were analyzed.

Want to know which bit of your brain thinks about sports cars? No problem! Intrigued to know which part's engaged when you think about baseball? Easy! What about about sex? Simple! The apps shows thousands of activities, ideas and objects in a semantic cloud: click on one, and it shows you which areas of the brain were activated by certain things. It's an amazing resource for researchers — and a hell of a lot of fun to play around with, too. [Semantic Movies]